To rule out internal interference try unscrewing the master NTE5 faceplate and plugging the router directly into the socket this reveals, with no other devices attached to the line. If you still have issues it’s either external or your homehub could be knackered.

All day yesterday I’ve had a strange problem where my BT broadband connection drops every few minutes – rebooting the homehub 3.0 has no effect but weirdly, making a phone call on the landline seems to re-establish the connection? For a few minutes at least. Why would this be?